<TITLE>CSPLib home page</TITLE>
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<SMALL>
The CSPLib site is mirrored in
<A HREF="http://www.csplib.org/">England</A> and the
<A HREF="http://www.cs.cornell.edu/home/selman/csplib/"> United States</A>.
<br> However, the US site is not updated as frequently as the English.
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<H1>CSPLib: a problem library for constraints</H1>


<TABLE>
<TR> <TD> maintained by
     <TD ALIGN=LEFT> <A HREF="http://www.dcs.st-and.ac.uk/~ipg/">
          <B>Ian P. Gent</B></A>
          <ADDRESS><a href="mailto:ipg@dcs.st-and.ac.uk">
          ipg@dcs.st-and.ac.uk</a></ADDRESS>
     <TD> and     
     <TD ALIGN=LEFT> <A HREF="http://www.cs.york.ac.uk/~tw/">
          <B>Toby Walsh</B></A> 
          <ADDRESS><a href="mailto:tw@cs.york.ac.uk">
          tw@cs.york.ac.uk</a></ADDRESS>
<TR>
<TD>
with help from
     <TD ALIGN=LEFT> <A HREF="http://simon.cs.cornell.edu/home/selman/">
          <B>Bart Selman</B></A> 
          <ADDRESS><a href="mailto:selman@cs.cornell.edu">
          selman@cs.cornell.edu</a></ADDRESS>
</TABLE>

CSPLib is funded by 
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the UK 
<A HREF="http://www.consnet.org/">
Network of Constraints</A>



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<P>
<H1> Overview </H1>
<P>
CSPLib is a
library of test problems for constraint solvers.
The library consists of: 
<UL>
<LI>  problems organized by <A HREF="subjects.html"> subject area</A>
      and <A HREF="problems.html"> problem number</A> 
<LI>  <A HREF="guidelines.html"> guidelines</A> for submitting new problems
<LI>  a paper about the library 
(in <A HREF="csplib.ps">postscript</A>
or <A HREF="csplib.html">html</A>) and
its <A HREF="bibref"> bibtex reference</A>

<BR>
(also available from the APES technical report <A HREF="http://www.cs.strath.ac.uk/~apes/apereports.html"> page</A>)
<LI>  a <A HREF="libraries.html"> list</A> of related benchmark libraries
<LI>  <A HREF="links.html"> links</A> to constraint solvers
<LI>  a <A HREF="mailing.html"> mailing list</A>  for news and updates
<LI>  a <A HREF="history.html"> history</A> of changes to the library
<LI>  a <A HREF="csplibv2.1.tar.gz"> tar file</A> of version 2.1 of
the library (and 
<A HREF="csplibv2.tar.gz">version 2.0</A>

</UL>
<P>
The main motivation for CSPLib is to focus research in constraints
away from purely random problems and onto more structured problems. 
<P>
To propose new entries, or to extend or correct existing
entries, pleas email 
<a href="mailto:csplib@cs.strath.ac.uk">
csplib@cs.strath.ac.uk</a>.
<P>



Number of different visitors to CSPLib:
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